It puzzles me that there are Laptops which are shipped with external physical Wi-Fi buttons. I see no real use of it, but it might have a historical explanation?! The only time one notice the external button is when one accidentally pushes the switch off, resulting in no data connection and “the internet is lost”. So my question is simply “Who needs an external on/off Wi-Fi button?”

Call me stupid but I didn't realize that a laptop at work had one of these, but I had no idea why the internet wasn't working. It was switched of haha.
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Matt RockwellFeb 18 '13 at 21:14

70

I want one on my phone so bad. I want external, hardware-bound switches for all the stuff that uses battery.
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kojiroFeb 18 '13 at 23:57

49

What I don't understand is when devices have these, but DON'T have a physical volume control.
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Nico BurnsFeb 19 '13 at 0:54

36

I use the Wi-Fi switches on my laptops all the time... Sometimes, I want to save power, force my computer to use an Ethernet cord, or avoid connecting to a public network, and it happens often enough that I missed my switch on my Mac (which has no Wi-Fi button) when I first got it.
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KevinFeb 19 '13 at 7:13

13

Frankly the process of turning off the Wi-Fi radio on Windows is a pain in the ass. Most of my users don't (or don't want to, more like) know how to do it, and just stay connected to Wi-Fi while they're plugged in to the LAN. This causes weird behaviour with network shares sometimes. I find it way easier to tell them to turn the switch off than to show them where the settings are (because they always forget!)
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SeyrenFeb 19 '13 at 8:43

14 Answers
14

Security

A hardware radio switch has security benefits to it in that when it is off, you know for a fact that nothing is connected to your laptop wirelessly. The radio switch usually turns off all wireless communication, including Bluetooth and 3G.

I have heard that this is a requirement in certain military environments, but I have not seen any evidence that this drove the development of the feature on any laptops.

Battery life

The physical button is not just to disable the wifi, but it should actually power off the device hardware.

When you disable wifi in your settings, the device is still powered up and using some power. It may not be a lot of power, but when you are commuting, every little bit helps. If you really want to save maximum battery life, then you want it to be consuming zero power.

Not for aircraft safety

Contrary to a commonly held belief, it is not for travel on aircraft. The FAA regulations apply only during takeoff and landing (and even those are currently being reconsidered). If this were a requirement for safety, every device allowed on an aircraft would have to have a hardware button - including mobile phones, tablets, and ebook readers.

Additionally, the rules for takeoff and landing specify that the devices themselves have to be turned off, not that the transmitters have to be turned off. So a switch would not comply with the current FAA rules on takeoff and landing.

Update: An FAA safety panel have just ruled that Wi-Fi is safe to use on airplanes, and the changes will likely be adopted soon. This just goes to show that it has nothing to do with safety, and never did.

Source: I am an electronic engineer with specialist courses in communication and wireless transmission. I have also taken a graduate level course in safety and security specifically in air transportation.

@BennySkogberg there are many applications for many business people that don't use cloud applications in the first place, and if you are travelling you may not have a wifi connection even if you wanted to use it. That is when you would turn off the wifi. I had many times that I did this on my Thinkpad.
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JohnGB♦Feb 18 '13 at 21:43

6

Some people actually prefer to work without connectivity as it limits distractions. It's actually rather annoying to work in an application that requires a data connection, and your only connection would lose in a race against a snail...
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Agent_9191Feb 19 '13 at 1:18

5

MOSFETs have very low leakage current. They are used to electrically power off entire subsystems in energy saving designs. A physical switch cannot noticeably beat this. However, what I like about physical switches is that you can operate them immediately and they will work for sure.
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Peter G.Feb 19 '13 at 7:41

1

It's amusing that laptops have lost the "portable computer" status to mobile devices so it's not immediately obvious that they would be used somewhere where there's no wifi available.
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JuhanaFeb 19 '13 at 11:29

2

Or if say travelling by train or bus where there's no local wifi you'd want to use or rely on, keeping the radio securely offline will prevent your computer to be hijacked by common wifi attacks...
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Oskar DuvebornFeb 19 '13 at 15:27

Besides the arguments others have listed (Aircraft requirements, power saving) we should not forget about security.

Before the tablet and smartphone era you had a great control over your computer in an emergency: if you pulled the UTP cable, you could guarantee that the computer is isolated from the network. If you pulled the power cord, you could guarantee that your computer is turned off.

With all these physical controls removed we arrive to a situation, where in case of a malware or hacking attack you have no option to stop your device from being remote controlled by the attacker, besides removing the battery (or smashing your device apart with a hammer if the battery is not removable).

With everything controlled by software, how can you be sure of your connection status? You might think you disabled wifi, but if your system is compromised, it can exchange data without you knowing it, while displaying that it's turned off. (Even if you turn your device off, it might just simulate it and darken the screen, and still run in the background.)

You might personally like thin clients and you might personally trust your software 100%, but there are people who don't, so why remove this option from them?

Some of the information contained in this post requires additional references. Please edit to add citations to reliable sources that support the assertions made here. Unsourced material may be disputed or deleted.

4

Security threats aren't so easy to detect. I can't imagine people constantly tailing their syslog while keeping a finger on the WiFi switch.
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Alexandre JasminFeb 19 '13 at 9:57

5

@AlexandreJasmin This is more like the case where you already know your system is compromised and want to try & find out how it got hacked in the first place.
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TC1Feb 19 '13 at 11:47

22

I can't believe this answer has so many upvotes... I don't know of any security professional who would call this an important "security feature." The iPad, for example, does not have a switch for WiFi; but no reasonable security professional would call that a security bug. This answer is just plain wrong; the real reason is simply to make it easy for non-technical users to save battery life.
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BlueRaja - Danny PflughoeftFeb 19 '13 at 17:49

4

Security would be the primary reason here too -- all external access to a device should be easily disabled physically as logical 'switches' can lie once a device is compromised.
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mikebabcockFeb 19 '13 at 22:57

6

Why don't desktop PC adapters for Wi-Fi (such as PCI cards) have switches on them, then? This type of security matters only for laptops?
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KazFeb 20 '13 at 23:52

Airplanes

These switches allow you to disable wireless transmitters without first turning them on in the middle of a flight, when their use may be prohibited.

There seems to be some consternation regarding this answer. I have reworded it to address some of the concerns that have been voiced. In addition...

I'm not saying that any rules regarding the use of wireless devices during flight are justified, only that they exist.

I'm not saying that any specific organization (such as the FAA) has made rules regarding the use of wireless devices during flight, only that some organizations (perhaps individual airlines) have put them in place and that they affect a significant number of air travelers.

I do not mean to suggest that this use case is the original or only reason for these switches, only that it is a valid use case.

Some of the information contained in this post requires additional references. Please edit to add citations to reliable sources that support the assertions made here. Unsourced material may be disputed or deleted.

14

Could you please provide some source for this? I've only ever seen it referred to as a power saving measure my any manufacturer.
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JohnGB♦Feb 19 '13 at 0:00

On flights I have been on, they say all electronic devices must be off for take-off and landing, and can only be turned on in-between if they are already in flight-mode. A switch like that is a convenience.
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AlbeyAmakiirFeb 19 '13 at 5:44

6

@TKKocheran It wouldn't knock a 747 out of the air, but it could affect navigation, it's just a safety precaution. I know some pilots that use their phone while flying, but they do have a rule about it: you have to shut the cockpit door...
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CoomieFeb 19 '13 at 6:20

In Emergency Situations
Sometimes you need to turn off your internet connection as fast as possible. For example, you download a software, then double click on it, and then you realize that it is not the genuine .exe file but it is a malicious file. In this situation, you may want to turn of your connection as fast as possible, and it may take a very long time to turn off it via software.

To Start the System With Connection Initially Turned off
For example, you may have left the web tool of your social network or a torrent program open before hibernating your laptop; and they are prohibited in your workplace. In this situation, just turning off the Wi-Fi is a lot easier than removing the battery.

Power Consumption
If you are almost always using Ethernet connection, you may want to completely turn off Wi-Fi.

I think it is always good to have a lot of control on your system. Who wants not to have power and volume adjust buttons on his load speaker because he can already control them via OS? Or not to have brightness control on monitor, because he can change brightness through some installed software?

Wifi takes power. If you have limited battery life, being able to physically power-down the wifi card might buy you back a little power. Otherwise, the OS might continually poll the airwaves looking for a signal and draining the battery a little faster.

Couldn't this be done just as effectively through settings in the OS, similar to the way you would turn off wifi on a cell phone?
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Matt RockwellFeb 18 '13 at 21:18

8

Yes it can be done. Just as effectively? That part is debatable -- a switch is certainly easier to flip than having to do a handful of clicks and double-clicks to get to a settings menu somewhere. Also, a physical switch implies you are physically turning the power off, which might give one more peace of mind that flipping a virtual switch.
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Bryan OakleyFeb 18 '13 at 21:48

2

I would argue a physical switch gives you one more thing to worry about. My guess is that these switches were put on by hardware makers in the early days of wi-fi due to poor software/battery life problems, and they've never been removed.
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nielsbotFeb 18 '13 at 22:04

3

+1 this is the real reason, as cited by every laptop manufacturer ever... The average user hates short battery life, but doesn't know how to or want to go messing around with things in the control panel.
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BlueRaja - Danny PflughoeftFeb 19 '13 at 3:55

1

@kaz: assuming that the wifi device can actually be controlled by software. Perhaps they are using cheap hardware that can only be controlled by a physical switch.
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Bryan OakleyFeb 21 '13 at 2:07

No, but having a physical switch makes them more convenient.
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KevinFeb 19 '13 at 20:17

1

I'm surprised nobody has given that as an answer. It's convenient.
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Samuel Edwin WardFeb 19 '13 at 20:23

1

I don't think I've ever used a laptop that defaulted to wifi when it had a working wired connection.
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Dan NeelyFeb 19 '13 at 21:47

3

When I was at church, my laptop detected the church's wifi. I let it try to connect, but it required a password that I did not know. Oh well, no big deal. Sunday morning when I was trying to take notes, I kept getting interrupted because the wifi was trying to reconnect. Hitting that button stopped it. It was more convenient at that moment than finding the list of connections and deleting it. I can also imagine a time where a person is in pop-up hell and needs to pull that virtual cable to stop their browser's bad behavior.
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TecBratFeb 20 '13 at 1:56

Anyone who needs to work in an area where you're not allowed to transmit/receive RF needs one. Part of the building where I work has those restrictions. Phones/tablets aren't allowed inside that part of the building because (among other unrelated reasons) there's no way to visually check if if the radios are disabled while the devices are powered off/in standby/etc. The wifi switch on the side on the side of my laptop is a simple and idiot resistant method of doing so, although if they could go back to the more foolproof setup of no built in wifi and the use of express card/usb dongles to add it in the way they did a decade ago I suspect they would do so.

I have one of those USB dongles on my desktop computer; they aren't just a thing of the past. However, having the USB dongle as a default consumer option seems like a no-no for an age where everything is expected to be integrated.
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Joe Z.Feb 19 '13 at 14:53

@JoeZeng Agreed, I was only referring to their use on laptops where they're a very uncommon sight these days; but at my employer laptops with docking stations have been the standard for a number of years with desktops only provided in cases where a laptop isn't suitable.
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Dan NeelyFeb 19 '13 at 16:59

As easy as it is to turn WiFi off with a switch, it is just as easy to accidentally turn it back on. With mobiles, you have the airplane icon to show all transmitters of off.
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oatmealsnapMay 2 '13 at 16:31

@oatmealsnap Dell Latitudes have switches stiff enough that an accidental bump isn't likely to toggle it. The slider switch is color coded for easy inspection while the laptop is off. When the laptop is on and open there's a wifi light above the keyboard that gives similar notification to the indicator on a phone/tablet screen.
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Dan NeelyMay 2 '13 at 17:40

Also, if the laptop is docked and has a wired connection(?), flipping the external wifi switch only triggers a popup saying "you also need to do X to enable wifi". (Just tested a minute ago.)
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Dan NeelyMay 2 '13 at 17:46

For me it has worked several times to re-initiate Wifi. Remember that most laptops use third party components, have dozens of configurations, which create dependencies. The status bar icon sometimes is not reliable, as it depends on the actual system state if it will work or not. Hardware switches turn off the device power, so it is way better for resetting. Just not to reboot every time when wifi connectivity fails.

I'm sure that works. Though I can't imagine the designers adding a physical switch just so you can reset a flaky WiFi adapter. If there's a firmware, driver or circuit design issue that requires frequent reboots they really should get it fixed.
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Alexandre JasminFeb 19 '13 at 10:12

2

"Should" does not mean they can... Users can install OEM drivers etc, which may cause problems in a specific configuration. And of course users would blame laptop manufacturer. I really think this is one of the key reasons for placing the switch.
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Dominik OslizloFeb 19 '13 at 10:22

I think your target audience influences the importance of a switch like this. A user that is not constantly in wifi might be depend on a switch like this to deter system tray notices about "no network". In that case, a physical guarantee of no alerts or interruptions might be valuable.

As a "thing", the dedicated wifi off-switch seems to be on it's way out. Smartphones don't have them, and the PS Vita ditched the wi-fi button (though notably the 3DS has a wifi button now).

To me the PSP was a great case study in why these things were annoying. I would constantly have to turn on the Wi Fi switch; it was slightly easier to turn off than on, so the switch often ended up resting in the off position. The OS spit out an ugly error message and required you to move a physical switch because it was hardware, not software, disabling the wifi device.

The PS Vita has a much more pleasant Wi Fi set up; you can manually turn it off via software, and it's automatically disabled in games that don't support it (for battery reasons I suppose).

The nice thing about software controlled Wi Fi is that if the setting is off and the user tries to perform an action that requires Wi Fi, Wi Fi can be re-enabled inside the GUI. No groping for a button, no taking your hands off the typical controls, no "okay...where the hell is the Wi Fi button". The software solution comes up Just In Time and requires no dedicated button in a world where external controls are expected to be few and precious.

Some have mentioned that you can power off the device hardware...but most devices can do that anyway. Smart phones already do this, though I'm not sure if Windows or Mac do it by default.

On their way out, sounds like a relief. The next laptop (No Surface RT for me) will not have a Wi-Fi off button switch. I will look close before buying. Thanx Ben!
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Benny Skogberg♦Feb 18 '13 at 21:47

2

"On its way out". Thanks for the warning. I'll make sure my next laptop has one of these buttons before I buy.
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BoannFeb 20 '13 at 13:22

2

'no "okay...where the hell is the Wi Fi button"' come on, how long can it take to find that? I'd rather say a software switch is inconvenient to find, particularly in fullscreen applications that can't usually be expected to anticipate this need. Then it may be unresponsive, etc. etc. (perhaps not in well-designed PS Vita games, but it's not rare in PCs).
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leftaroundaboutFeb 20 '13 at 22:55

The most plausible hypothesis is that the switch is needed on laptops for historic reasons, and also because laptops are flexible and run multiple operating systems.

Let us take it for granted that a device needs a switch for disabling the Wi-Fi transmitter, whether that switch be soft or hard.

Historic reasons for the hardware switch: Windows came before Wi-Fi, and Wi-Fi has been clumsily integrated into Windows. By contrast, modern mobile devices were designed with the assumption that the hardware has Wi-Fi and that Wi-Fi is very important to the user. The software switch is easy to find. For instance on Android devices, it is on the notification bar of the home screen.

Bottom line: the easiest, quickest way to disable Wi-Fi on a random laptop is in fact to use that switch, rather than to navigate through the obtuse user interface of whatever version of Windows it is running (possibly with vendor-specific Wi-Fi crapware), or that of some unfamiliar operating system that the owner has installed on the system.

Analogy: Why do monitors have an off button? Can't you just put the OS to sleep, and the monitor will shut down by itself? Traditionally, OS's don't sleep and monitors have power buttons, and different versions of OS's have different obtuse ways to be put to sleep. Sometimes automatic sleep is unreliable, too. Ironically, this feature is missing from laptops! There have been times I wanted a switch to turn off the monitor of a laptop! Switches are good, damn it.

Anything in a system that can happen accidentally because of poor design, need to be changed. Imagine the confusion when "the internet" suddenly is disconnected, and you have no clue what happened. There is a real need for making buttons that will be switched on/off intentially only, and not by accident.

Sometimes one wonders if manufacturers overlooked this problem or just didn't take care of insight from customer support.

Who needs an external on/off Wi-Fi button?

Fewer and fewer people I'd say, since the ones mention before like airplanes, would most likely decrease in number. There are more and more airplanes having WiFi on board. Safety? Who knows when your being hacked? Probably only when you want to disconnect yourself from the online world - not receiving e-mails or facebook notifications since your watching a nice movie. Intentially - not accidental!

The FAA is actually reevaluating the use of wifi/etc on planes during takeoff/etc. so that might become a non-issue as well (or might not; my impression is they simply haven't actually done the research necessary, so they don't actually know either way).
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Ben Brocka♦Mar 8 '13 at 14:33

It is also because of the 'mobile devices' like laptops that were being used since so long time. They had always got a Wi-Fi button somewhere near the keyboard pad that could be activated by pressing while the laptop is ON and working.

Probably, the use of external button was one more way of finding a
relationship with the old laptop users who had shifted to smartphone
use and feel better to have an external WiFi button to be tapped and
put it on while travelling and in congested places where they might
not care to go to a specific widget or settings to get the WiFi
Activated by a press of a finger on the screen. New users might find
the button intimidating.

In Broad daylight and in a place buzzing
with activities, it becomes difficult often to read the LED screen.
Hence it might be better to have an external button which is a
shortcut to putting Wifi on/off. May be people can then move to a
place where they can browse freely.